The invention relates to a heterostructure semiconductor laser diode with a sequence of layers formed on a substrate, a laser-active layer arranged between enclosing layers of opposite conductivity type, and a cover layer disposed on the side of the sequence of layers facing away from the substrate.
A heterostructure semiconductor laser diode with a V-groove-shaped recess is known from German Pat. No. 2,822,146. The current flowing in the forward direction of the semiconductor laser diode is restrictred to a narrow strip-shaped area of the laser-active layer. The active area or strip is pumped up to the resonator mirrors. Heat is generated at the mirrors by surface recombination and the overpopulation in the valence or conduction band is simultaneously reduced. As a result, the directly generated heat together with the absorption induced by the absence of overpopulation cause a gradual degradation of the mirrors with relatively low output power. The thus produced laser structure is based on an n-conducting substrate.